Antenna device having ultra wide bandwidth characteristics

Abstract

An antenna device having ultra wide bandwidth characteristics includes: a dielectric substrate having first and second surfaces that are opposite to each other in a normal direction; a radiating element formed on the first surface of the dielectric substrate and defining an axis perpendicular to the normal direction; and a grounding element formed on the second surface of the dielectric substrate and cooperating with the radiating element to define first and second imaginary slots in the dielectric substrate. The first and second imaginary slots extend in the normal direction from the first surface to the second surface of the dielectric substrate, and are respectively disposed at two opposite sides of the axis.

1. An antenna device having ultra wide bandwidth characteristics, comprising:
 a dielectric substrate having first and second surfaces that are opposite to each other in a normal direction; 
 a radiating element formed on said first surface of said dielectric substrate, defining an axis perpendicular to said normal direction, and having a peripheral edge that has an inner portion; and 
 a grounding element formed on said second surface of said dielectric substrate and having a peripheral edge that has an inner portion facing toward said inner portion of said peripheral edge of said radiating element; 
 wherein said inner portion of said peripheral edge of said grounding element cooperates with said inner portion of said peripheral edge of said radiating element to define first and second imaginary slots in said dielectric substrate, said first and second imaginary slots extending in said normal direction from said first surface to said second surface of said dielectric substrate, and being respectively disposed at two opposite sides of said axis. 
 
     
     
       2. The antenna device of  claim 1 , wherein said radiating element has a first part that defines a first tip at said inner portion of said peripheral edge of said radiating element, said axis passing through said first tip. 
     
     
       3. The antenna device of  claim 2 , wherein said first imaginary slot diverges from said first tip in a first direction transverse to said axis, said second imaginary slot diverging from said first tip in a second direction opposite to said first direction. 
     
     
       4. The antenna device of  claim 3 , wherein said first part of said radiating element is substantially triangular in shape and further defines a second tip, said radiating element further including a second part that is substantially square in shape and that extends from said second tip in a direction parallel to said axis. 
     
     
       5. The antenna device of  claim 4 , wherein said first part of said radiating element further defines a third tip, and has a first side extending between said first and second tips and confining one side of said first imaginary slot, and a second side extending between said first and third tips and confining one side of said second imaginary slot. 
     
     
       6. The antenna device of  claim 5 , wherein said grounding element has a first part that extends in a direction parallel to said axis and that has a first end portion aligned with said second part of said radiating element in said normal direction, and a second end portion opposite to said first end portion, said grounding element further including a second part that extends from said second end portion of said first part of said grounding element and that is aligned with said first part of said radiating element along said axis. 
     
     
       7. The antenna device of  claim 6 , wherein said second part of said grounding element has a first segment extending transversely from said second end portion of said first part of said grounding element and passing through said axis, and a second segment reduced in dimension from said first segment toward said first tip of said first part of said radiating element and having an edge that is aligned with said first tip of said first part of said radiating element in said normal direction, said second segment of said second part of said grounding element cooperating with said first part of said grounding element and said first part of said radiating element to define said first imaginary slot, said second segment of said second part of said grounding element cooperating with said first part of said radiating element to define said second imaginary slot. 
     
     
       8. The antenna device of  claim 7 , wherein said second segment of said second part of said grounding element has a first section that is reduced in dimension from said first segment and that is trapezoid in shape, and a second section that extends from said first section and that defines said edge of said second segment. 
     
     
       9. The antenna device of  claim 8 , wherein said second section of said second segment is rectangular in shape and passes through said axis. 
     
     
       10. The antenna device of  claim 8 , wherein said second section of said second segment is semi-circular in shape and passes through said axis. 
     
     
       11. The antenna device of  claim 8 , wherein said second section of said second segment has a first portion that is square in shape and that is disposed at one of said sides of said axis, and a second portion that is triangular in shape and that is disposed at the other of said sides of said axis. 
     
     
       12. The antenna device of  claim 7 , further comprising a feeding element that is formed on said first surface of said dielectric substrate and that extends from said first tip of said radiating element along said axis. 
     
     
       13. The antenna device of  claim 12 , wherein said first segment of said second part of said grounding element has an outer side that is distal from said second segment of said second part of said grounding element, said feeding element having a terminal end that is aligned with said outer side of said first segment in said normal direction. 
     
     
       14. The antenna device of  claim 6 , further comprising at least one conductive connecting line that is connected to and that extends from said second part of said radiating element through said dielectric substrate to connect with said first end portion of said first part of said grounding element.